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Old 12-20-2018, 07:26 AM   #11
NOALB
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Speaking as a user of self-centering pedals, I was curious and had to test the AP yaw channel with Rudder Trimmer off (I've only ever had it on). At least in Central Position Trimmer Mode, it seems to do absolutely nothing. So if you want the benefit of the heading hold, it seems Rudder Trimmer must be enabled. I personally would never forgo the yaw AP channel because it's actually pretty amazing; once it reaches its 20% authority limit, it switches to "displacement mode" (as the Dash 10 refers to it [2-46]), allowing the system to move the pedals to adjust the trim through its entire range, effectively giving the yaw channel 100% authority. If you take it a bit slow, it's possible to transition through all flight regimes from ground to cruising at altitude to landing while not touching the pedals once.

Quote:
Originally Posted by Z4ng3tsu View Post
[...]You were suggesting to turn off the rudder trim in the options. What is the closest to reality, option on or off ?
Certainly on. Unless I'm mistaken and it's still possible to take advantage of the yaw AP channel with Rudder Trimmer off...

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Originally Posted by 3WA View Post
[...]Might be better to do fast maneuvers in FD mode, where there is just damping.
Yeah, trying to fight the Ka-50's AP is just painful. I consider FD mode so essential I have it bound to my stick's weapon release button and I press it whenever I need to do, well, nearly any maneuver that isn't just adjusting my trim a bit. Keep in mind that holding the trim button has basically the same effect on the AP as activating FD mode, which is why it makes the process so smooth. Hold trim, adjust attitude/heading, step on the ball, release trim, perfect coordinated flight (even works with the Mi-8 most of the time as well for me)

Quote:
Originally Posted by Z4ng3tsu View Post
I tested for the Mi-8. It seems to work a little more when keeping the trim button pushed when changing course. But the most effective is to reset the trim after a turn and then trimming the aircraft. [...]
As the manual states (pg 221),
"In the Mi-8 depression and holding of the trimmer button do not engage alignment mode of the autopilot, as it is done in the Ka-50. I.e. trimmer as object is not interacting with autopilot at all."
The trimmer shouldn't affect the AP whatsoever; the smoothness of your trimming only has to do with your trimming method and settings. You really shouldn't have to reset the trim at all unless you suddenly need to do some hard maneuvering and need the entire range of control.

If you have a self-centering stick which returns to center quickly and accurately when you let go, I'd recommend giving Central Position Trimmer Mode a try if you haven't. As far as smoothness goes, it's the next best thing to a springless or actual FFB stick.






And now the big one: It took me a little while, but I figured out why the yaw AP channel is sometimes inconsistent in setting a new heading, and it's rather strange; if you look at the АП-34Б control panel, at the centering knobs with the small windows just above them, you'll notice that when any particular channel isn't engaged, the indicator disks in the windows rotate on their own, corresponding to the attitude of the helicopter (e.g., when the helicopter's heading is steady, the indicator dial under "НАПРАВЛЕНИЕ" won't be rotating). If you turn and change your heading quickly, you'll notice that the indicator takes some time to catch up to the new detected heading. Halting the disk's rotation too early by activating the autopilot channel (or releasing the rudder pedals if the AP was already active) will cause the system to lock to a point between its last setting and the new heading (for example, making a rapid turn from a heading of 5° to a heading of 90° and then immediately activating the yaw AP channel could cause the system to "lock" onto a heading of 30°).


In practice, what this means is that every time you make a major adjustment to your attitude/heading, you must watch the indicator window to make sure the dial has stopped rotating, otherwise you may inadvertently set the channel to a point that's too "early" in the arc. If the yaw AP setting is too far off your actual heading, it will indeed cause the pedals to go massively out of alignment and destabilize the helicopter.



Now I have a mouse with a freewheeling scroll wheel, so I wanted to mess with the AP a bit since I can shift+scroll like nobody's business
As it turns out, the indicator might not actually be realistically limited in how much it can lag behind. Turning the centering knob with a good, solid flick of the wheel resulted in the system taking over a minute and a half to realign. The dial can also be sped up to expedite realignment by turning it in the direction of your turn.


Unrelated, but the autopilot indicator that shows up with the controls indicator seems to feature Cyrillic characters regardless of language or cockpit settings, including the 'Л' and 'П' indicators which show up in the heading AP channel when the system enters "displacement" mode to move the pedals. Further trivia: this seems to be the only indicator of when the pedals are being moved by the AP (other than seeing them move of course).






OKAY, this is the last of the text wall; it's a question for any devs or experts who may be reading: In the Dash 10 (2-46), it states "When the pilot’s feet are on the pedals, the sub-pedal microswitches activate, the force trim disengages, and the yaw channel operates in stabilization mode."
So, my question is, is the "stabilization mode" implemented in the sim in any way? As I understand it, the pedal microswitches are simulated by the AP disengaging when the pedals are moved (always wondered why that couldn't be implemented with an additional option of having the toe brakes activate the switches), but I'm not noticing any additional "stabilization" when the pedals are off-center with the AP on. Is the Dash 10 or my reading comprehension just off base here?
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Old 12-20-2018, 07:31 PM   #12
AlphaOneSix
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Quote:
Originally Posted by NOALB View Post
OKAY, this is the last of the text wall; it's a question for any devs or experts who may be reading: In the Dash 10 (2-46), it states "When the pilot’s feet are on the pedals, the sub-pedal microswitches activate, the force trim disengages, and the yaw channel operates in stabilization mode."
So, my question is, is the "stabilization mode" implemented in the sim in any way? As I understand it, the pedal microswitches are simulated by the AP disengaging when the pedals are moved (always wondered why that couldn't be implemented with an additional option of having the toe brakes activate the switches), but I'm not noticing any additional "stabilization" when the pedals are off-center with the AP on. Is the Dash 10 or my reading comprehension just off base here?
The -10 is incorrect. While I love the TSMO manuals, they do occasionally misinterpret the Russian manuals. Stabilization duty is when the pilot's feet are OFF the pedals and the yaw channel is maintaining aircraft heading.
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Old 12-21-2018, 06:02 AM   #13
NOALB
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Originally Posted by AlphaOneSix View Post
The -10 is incorrect. While I love the TSMO manuals, they do occasionally misinterpret the Russian manuals. Stabilization duty is when the pilot's feet are OFF the pedals and the yaw channel is maintaining aircraft heading.
Thanks a bunch - really appreciate all you contribute here, especially the presentations which have been invaluable to my understanding of these systems. And such good pictures too!
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